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SM 25x275 [2xM8] / N42 - magnetic separator

magnetic separator

Catalog no 130294

GTIN: 5906301812876

5

Diameter Ø [±0,1 mm]

25 mm

Height [±0,1 mm]

275 mm

Weight

0.01 g

762.60 with VAT / pcs + price for transport

620.00 ZŁ net + 23% VAT / pcs

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SM 25x275 [2xM8] / N42 - magnetic separator

Specification/characteristics SM 25x275 [2xM8] / N42 - magnetic separator
properties
values
Cat. no.
130294
GTIN
5906301812876
Production/Distribution
Dhit sp. z o.o.
Country of origin
Poland / China / Germany
Customs code
85059029
Diameter Ø
25 mm [±0,1 mm]
Height
275 mm [±0,1 mm]
Weight
0.01 g [±0,1 mm]
Manufacturing Tolerance
± 0.1 mm

Magnetic properties of material N42

properties
values
units
coercivity bHc ?
860-955
kA/m
coercivity bHc ?
10.8-12.0
kOe
energy density [Min. - Max.] ?
318-334
BH max KJ/m
energy density [Min. - Max.] ?
40-42
BH max MGOe
remenance Br [Min. - Max.] ?
12.9-13.2
kGs
remenance Br [Min. - Max.] ?
1290-1320
T
actual internal force iHc
≥ 955
kA/m
actual internal force iHc
≥ 12
kOe
max. temperature ?
≤ 80
°C

Physical properties of NdFeB

properties
values
units
Vickers hardness
≥550
Hv
Density
≥7.4
g/cm3
Curie Temperature TC
312 - 380
°C
Curie Temperature TF
593 - 716
°F
Specific resistance
150
μΩ⋅Cm
Bending strength
250
Mpa
Compressive strength
1000~1100
Mpa
Thermal expansion parallel (∥) to orientation (M)
(3-4) x 106
°C-1
Thermal expansion perpendicular (⊥) to orientation (M)
-(1-3) x 10-6
°C-1
Young's modulus
1.7 x 104
kg/mm²

Shopping tips

The magnetic separator, namely the magnetic roller, uses the force of neodymium magnets, which are embedded in a casing made of stainless steel usually AISI304. Due to this, it is possible to efficiently separate ferromagnetic particles from different substances. An important element of its operation is the repulsion of N and S poles of neodymium magnets, which allows magnetic substances to be targeted. The thickness of the embedded magnet and its structure pitch determine the range and strength of the separator's operation.
Generally speaking, magnetic separators are designed to separate ferromagnetic particles. If the cans are made from ferromagnetic materials, a magnetic separator will be effective. However, if the cans are made of non-ferromagnetic materials, such as aluminum, the separator will not effectively segregate them.
Yes, magnetic rollers find application in the food sector to clear metallic contaminants, including iron fragments or iron dust. Our rods are built from durable acid-resistant steel, EN 1.4301, approved for use in food.
Magnetic rollers, otherwise cylindrical magnets, are used in food production, metal separation as well as waste processing. They help in removing iron dust during the process of separating metals from other wastes.
Our magnetic rollers are built with neodymium magnets placed in a stainless steel tube casing of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar will be with M8 threaded openings, allowing for simple mounting in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of magnetic properties, magnetic bars stand out in terms of flux density, magnetic force lines and the field of the magnetic field. We produce them in materials, N42 and N52.
Generally it is believed that the stronger the magnet, the better. Nevertheless, the value of the magnet's power depends on the height of the used magnet and the quality of the material [N42] or [N52], as well as on the area of application and expected needs. The standard operating temperature of a magnetic bar is 80°C.
When the magnet is thin, the magnetic force lines are short. Otherwise, when the magnet is thick, the force lines are extended and reach further.
For constructing the casings of magnetic separators - rollers, usually stainless steel is employed, especially types AISI 316, AISI 316L, and AISI 304.
In a saltwater contact, type AISI 316 steel exhibits the best resistance thanks to its excellent anti-corrosion properties.
Magnetic bars stand out for their specific arrangement of poles and their capability to attract magnetic particles directly onto their surface, as opposed to other separators that often use complex filtration systems.
Technical designations and terms pertaining to magnetic separators include among others magnet pitch, polarity, and magnetic induction, as well as the steel type applied.
Magnetic induction for a magnet on a roller is measured using a teslameter or a gaussmeter with a flat Hall-effect probe, seeking the highest magnetic field value near the magnetic pole. The result is verified in a value table - the lowest is N30. All designations below N27 or N25 suggest recycling that doesn't meet the standard - they are not suitable.
Neodymium magnetic bars offer a range of benefits such as higher attracting power, longer lifespan, and effectiveness in separating fine metal particles. Disadvantages may include the need for regular cleaning, higher cost, and potential installation challenges.
By ensuring proper maintenance of neodymium magnetic rollers, you should washing after each use, avoiding temperatures above 80 degrees. The rollers our rollers have waterproofing IP67, so if they are not sealed, the magnets inside can oxidize and weaken. Magnetic field measurements should be carried out every two years. Care should be taken, as there is a risk of finger injury. If the protective tube is only 0.5 mm thick, it may wear out, which in turn could lead to problems with the magnetic rod seal and product contamination. The range of the roller is equal to its diameter: fi25mm gives an active range of about 25mm, while fi32 gives an active range of about 40mm.
A magnetic roller is a magnetic separator made from a neodymium magnet enclosed in a cylindrical stainless steel housing, used for separating ferromagnetic contaminants from raw materials. They are used in the food industry, recycling, and plastic processing, where the removal of iron metals and iron filings is essential.

Advantages and disadvantages of neodymium magnets NdFeB.

Apart from their notable holding force, neodymium magnets have these key benefits:

  • They do not lose their strength nearly ten years – the decrease of strength is only ~1% (according to tests),
  • They show strong resistance to demagnetization from external field exposure,
  • The use of a mirror-like silver surface provides a refined finish,
  • They possess significant magnetic force measurable at the magnet’s surface,
  • They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
  • Thanks to the freedom in shaping and the capability to adapt to individual requirements, neodymium magnets can be created in different geometries, which increases their application range,
  • Important function in new technology industries – they are utilized in computer drives, electric motors, clinical machines as well as sophisticated instruments,
  • Thanks to their power density, small magnets offer high magnetic performance, with minimal size,

Disadvantages of magnetic elements:

  • They are prone to breaking when subjected to a sudden impact. If the magnets are exposed to shocks, we recommend in a protective case. The steel housing, in the form of a holder, protects the magnet from breakage and strengthens its overall robustness,
  • They lose magnetic force at elevated temperatures. Most neodymium magnets experience permanent decline in strength when heated above 80°C (depending on the dimensions and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
  • They rust in a humid environment. If exposed to rain, we recommend using encapsulated magnets, such as those made of plastic,
  • The use of a protective casing or external holder is recommended, since machining threads in neodymium magnets is difficult,
  • Health risk linked to microscopic shards may arise, when consumed by mistake, which is notable in the health of young users. It should also be noted that small elements from these magnets have the potential to complicate medical imaging if inside the body,
  • High unit cost – neodymium magnets are more expensive than other types of magnets (e.g., ferrite), which can restrict large-scale applications

Exercise Caution with Neodymium Magnets

Dust and powder from neodymium magnets are highly flammable.

Avoid drilling or mechanical processing of neodymium magnets. Once crushed into fine powder or dust, this material becomes highly flammable.

Under no circumstances should neodymium magnets be placed near a computer HDD, TV, and wallet.

Strong magnetic fields emitted by neodymium magnets can destroy magnetic storage media such as floppy disks, credit cards, magnetic ID cards, cassette tapes, video tapes, or other devices. They can also damage televisions, VCRs, computer monitors, and CRT displays. Avoid placing neodymium magnets in close proximity to electronic devices.

It is crucial not to allow the magnets to pinch together uncontrollably or place your fingers in their path as they attract to each other.

Magnets will bounce and contact together within a distance of several to around 10 cm from each other.

Neodymium magnets are noted for their fragility, which can cause them to crumble.

Neodymium magnetic are delicate as well as will crack if allowed to collide with each other, even from a distance of a few centimeters. Despite being made of metal and coated with a shiny nickel plating, they are not as hard as steel. In the case of a collision between two magnets, there can be a scattering of small sharp metal fragments in different directions. Protecting your eyes is essential.

 Maintain neodymium magnets away from children.

Not all neodymium magnets are toys, so do not let children play with them. In the case of small magnets, they can be swallowed and cause choking. In such cases, the only solution is to undergo surgery to remove the magnets, and otherwise, it can even lead to death.

The magnet coating contains nickel, so be cautious if you have a nickel allergy.

Studies show a small percentage of people have allergies to certain metals, including nickel. An allergic reaction often manifests as skin redness and rash. If you have a nickel allergy, try wearing gloves or avoid direct contact with nickel-plated neodymium magnets.

Neodymium magnets can become demagnetized at high temperatures.

Although magnets are generally resilient, their ability to maintain their magnetic potency can be influenced by factors like the type of material used, the magnet's shape, and the intended purpose for which it is employed.

Keep neodymium magnets away from people with pacemakers.

Neodymium magnets produce strong magnetic fields that can interfere with the operation of a heart pacemaker. Even if the magnetic field does not affect the device, it can damage its components or deactivate the entire device.

Do not bring neodymium magnets close to GPS and smartphones.

Magnetic fields generated by neodymium magnets interfere with compasses and magnetometers used in navigation, as well as internal compasses of smartphones and GPS devices.

Neodymium magnets are the most powerful magnets ever invented. Their power can surprise you.

Familiarize yourself with our information to properly handle these magnets and avoid significant injuries to your body and prevent disruption to the magnets.

Pay attention!

Please see the article - What danger lies in neodymium magnets? You will learn how to handle them properly.

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e-mail: bok@dhit.pl

tel: +48 888 99 98 98